<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>insertAfter</title>
</head>
<body>
    <div id="content">在content后面插入p元素</div>
    <script>
        const insertAfter = (el,html) => el.insertAdjacentHTML('afterend',html);
        insertAfter(document.getElementById("content"),'<p>after</p>');
    </script>
</body>
</html>